Compost helps rangeland lock up carbonLeave a Comment
By Carolyn Lochhead Updated 8:22 pm, Saturday, October 18, 2014
A compost experiment that began seven years ago on a Marin County ranch has uncovered a disarmingly simple and benign way to remove carbon dioxide from the air, holding the potential to turn the vast rangeland of California and the world into a weapon against climate change.
The concept grew out of a unique Bay Area alignment of a biotech fortune, a world-class research institution and progressive-minded Marin ranchers. It has captured the attention of the White House, the Brown administration, the city of San Francisco, officials in Brazil and China, and even House Republicans, who may not believe in climate change but like the idea that “carbon farming” could mean profits for ranchers.
Experiments on grazing lands in Marin County and the Sierra foothills of Yuba County by UC Berkeley bio-geochemist Whendee Silver showed that a one-time dusting of compost substantially boosted the soil’s carbon storage. The effect has persisted over six years, and Silver believes the carbon will remain stored for at least several decades.
The experiments were instigated by John Wick and his wife, Peggy, heiress to the Amgen biotech fortune, on a 540-acre ranch they bought in Nicasio. What began as a search for an artist’s studio turned into a seven-year, $8 million journey through rangeland ecology that has produced results John Wick calls “the most exciting thing I can think of on the planet right now.”
The research showed that if compost from green waste — everything from household food scraps to dairy manure — were applied over just 5 percent of the state’s grazing lands, the soil could capture a year’s worth of greenhouse gas emissions from California’s farm and forestry industries.
The effect is cumulative, meaning the soil keeps absorbing carbon dioxide even after just one application of compost, the researchers found. In theory, Silver calculates, if compost made from the state’s green waste were applied to a quarter of the state’s rangeland, the soil could absorb three-quarters of California’s total annual greenhouse gas emissions.
“For a lot of people, this sounds a little fantastic,” Silver said. “There’s nothing magic about it.”
Soil is a major source of carbon, “and we’ve been bleeding it into the atmosphere for many, many years through plowing, overgrazing and poor agricultural practices,” Silver said. “So anything we can do to get some of that carbon back into the soil is going to be beneficial.”….
by Katie Valentine Posted on October 22, 2014
According to research, if compost were applied to 5 percent of California’s land used for livestock grazing, it could result in a year’s worth of emissions from farm and forestry industries being captured. …